ISupportIncrementalLoading in combination with VariableSizedWrapGrid

Question

I have an ObservableCollection<T> that implements the ISupportIncrementalLoading interface.

When I bind this collection to a normal gridview, everything works fine.

But when I change the ItemsPanel template to VariableSizedWrapGrid. Incremental loading no longer works.

Xaml that works:

 <ItemsPanelTemplate> <VirtualizingStackPanel Orientation="Horizontal"/> </ItemsPanelTemplate> 

Xaml that does not work:

 <ItemsPanelTemplate> <VariableSizedWrapGrid Orientation="Vertical" ItemHeight="250" ItemWidth="250" Margin="0,0,80,0"/> </ItemsPanelTemplate> 

I also found this and this . The VariableSizedWrapGrid statement does not support ISupportIncremetalLoading .

Is there anyone who wrote VariableSizedWrapGrid that supports incremental loading? Or an open source solution?

Answer 1

There are only two panels that support incremental loading: VirtualizingStackPanel and WrapGrid. I do not know about any open source solution.

Answer 2

It is not supported, because the panel itself must be able to virtualize elements. Since insatemplates insice VariableSizedWrapGrid are different, it is not possible to virtualize, so every element you want to make must be present at the beginning.